fitz gibbon



A. L. FITZ GIBBON.

TRACTION WHEEL.

APPLICATION men MM2, 1919.

Patented Dec. 2, 1919.

2 SHEETS-SHEET I.

iTEn sTATEs PATENT oFFi/cit.

ARTHUR I.. FITz GIBBoN, or WAsHINGTort, DISTRICT or COLUMBIA.

TRACTlON-WHEEL.

clear, and exact description of the same,

reference being had to the accompanying drawings, forming a part of thisspecification.

This invention relates to vehicle wheels and especially to wheelsadapted for use on tractors and other heavy vehicles. The

tread portions of wheels used on vehicles of this character are usuallyprovided with a series of projections adapted tol penetrate the learth,when the vehicle is operated in the eld, to afford the wheel a betterhold or grip on the earth, thus increasing the tractive power ofthewheel. Vhen, however, the vehicle is propelled over a road,

the tendency of the projections to penetrate the road surface causes anundue amount of wear on the road. To prevent this, the present inventioncontemplates the provision of a wheel in which the ground penetratingelements or members can be projected beyond the periphery of the wheelwhen necessary or they can be retracted to a position within the wheelwhere they can not come in contact with the road surface.

The primary object of the invention is to provide a structure in whichthe penetrating elements or members will normally be yieldingly held intheir retracted7 inoperative position but when they have been projectedto their operative position they,

will be locked in that position by the rotative force of the wheel asthey successively come in contact with the ground. Another object is toprovide a mechanism of this character that can readily be applied to thedriving wheels or the driven wheels of the vehicle. These objects willbe clearly set forth in the following description of the embodiment ofthe invention shown in the accompanying drawings, in which descriptionother objects will be particularly pointed out or will otherwise appear.

In said drawings:

Figure 1 is a side elevation of a wheel with the present inventionapplied thereto, only one wheel being shown as the mechanism is the samewhether it be applied to a driving wheel or a driven one;

Specification of Letter's Patent.

Patented Dee. 2, '1919.

Appilcation led May 2, 1919. Serial No. 294,224.

Fig. 2 is a sectional view on lthe line 2-2, of Fig. 1, the housing orcasing of the mechanism for actuating the penetrating members beingshown in plan;

Fig. 3 is a detail sectional view, in a vertical plane, of the housinshowing the mechanism for projecting t e penetratin members into theiroperative position, sai mechanism being shown in the position itoccupies when the lpenetrating members are in their retracted,inoperative position;

Fig. 4.- is a view similar to Fig. 3 showing the projecting mechanism inthe position it occupies when the 4penetrating members have been -movedto their operative position; Fig. 5 is a sectional view on the line 5-5of Fig. 3;

Figs. 6 and 7 are detail views of the ground penetrating members intheir inoperative and operative positions, respectively, showing themeans oy which said members are locked in their operative positlon; y

Fig. 8 is a detail view illustrating the manner in which the carrierbars of the ground penetrating members are mounted on the wheel. v

Like numerals indicate the same parts in the several views.

As stated, only one wheel is shown and in the present instance this isillustrated as one of the driving wheels, being adapted to be drivenfrom a suitable source of power by the sprocket wheel 11 mounted on theaXle 12 on which the vehicle frame 13 is mounted in any well knownmanner.

Secured to each of the alternate spokes 14 of the wheel is a pair ofbrackets 15 in -which are loosely and slidably mounted raadapted to beprojected through apertures 18 in the rim 19, these penetrating membersbeing preferably formed of a short bar of metal T-shape in cross sectionto obtain the greatest degree of rigidity. The inner ends 16b of thecarrier bars 16 are bent at right opposite to that in which the wheel isro their operative position they project beyond` angles in a directionopposite to the ends 16v and extend into ahousing 20 for the position.

sides 25, 26 secured thereto. The side 25 of the housing is provided atvits outer edge with an annular flange 27 which overlaps the outer edgeof a dust guard plate 28 mounted on the hub of the Wheel and providedwith openings 29 through which the ends 16" of the carrier bars extendinto the housing, the side 2 6 of the housing being shorter than theother side so as not to inf terfere with the carrier barsw'hen thelatter are revolved by the rotation of the wheel. To permit thepresentinvention to be ap- Normally these penetrating membersare\\`plied to the driving or driven wheels of the held in a positionWhere their ou r ends will lie within or substantially ush with thetread surface of the rim, vas shown in Fig. 6, and when they areprojected into the tread surface with the recesses `21 substantially inalinement with the rim. Howl ever, as the carrier bars 16 are looselymounted in brackets 15, (see Fig. 8) and are permitted a slight movementtoward and away from the walls of apertures 18, a spring 22 interposedbetween each of the carrier bars and one of the spokes will normallyhold the' recesses in the individual penetrating mem-v bers out ofengagement with the wall of the respective aperture in the rim. With thepenetrating members in their operative position, the rotation of thewheel brings them successively in contact with the ground whereupon thetension of springs 22 is overcome and the penetrating members aremomentarily held stationary while the rim continues to rotate, due tothe carrier bars of the penetrating members being loosely mounted intheir brackets. This continued advance of the rim forces the wall ofaperture 18 into the recess 21 in the individual penetrating members assaid members successively come in contact with the ground and are heldstationary, and locks that particular member, which is in contact withthe ground, in its projected position. The individual penetratingmembers remain locked until they have been withdrawn from the ground,when springs 22 will disengage the rim and recess.

To impart strength to the penetrating members, and to insure againsttheir becoming accidentally unlocked while in the ground, the bottomface 16 of the 'outer vehicle the hub is loosely mounted on the axle,and does not rotate therewith, the inner side 25 of the housing beingconnected to the frame of the vehicle by connecting.

lbars 30.

-to a ring 35 on the exterior of the housing adapted to be rocked b ahand lever 36 90 provided with a pawl 3 coperating with a toothedsegment38 for holding the lever in any desired position.- A pair. ofrigid links 39 are secured at their inner ends to each of pins 32, 33and at their outer ends they are attached to pins 40 secured in ci'rcularly arranged segmental Amembers 41, preferably four, which areinclosed or ,surrounded by a resilient, cylindrical metal band 42, theends of which overlap. each other andare disconnected to permit the bandto be expanded by an outward, radial movement of the segmental members41. The overlapped ends of the band 42 are tapered so that the peripheryofthe band forms a substantially true circular 'track or bearing surfacefor rollers 43 journaled in arms 44 attached to the Ainwardly extend-`ing end portions 16b of the carrier bars 16 of the penetratingmembers'.

Normally these various parts occupy the positions in which they areshown in Fig. 3, the ground penetrating members being in theirretracted, inoperative position, but when it is desired to move thevpenetrating 116 members to their projected, operative position the handlever 36 is moved forwardly, rocking rings 35 and 31 and moving pins 32,33 substantially in radial alinement with pins 40 inthe segmentalmembers, which 120 will cause links 39 to expand the segmental members,and band 42, to the positions in which they are shown in Fig. 4. Theexpansion of the ring 42 will move the inner ends 16b of carrier bars 16outwardly, thus 125 projecting the ground penetrating members into theiroperative position where they will be successively locked as heretoforedescribed. When it is desired to withdraw the penetrating members totheir retracted, 130

' readily designed Without departing from the spirit of the presentinvention.

What is claimed is:

1. In a vehicle wheel, the combination of ground penetrating membersadapted to.be brought successively in Contact with the ground, manuallycontrolled means for moving said members into operative posi-v tion, andmeans for successively locking said members in operative position by therotative force of thev Wheel as said members are brought into contactwith the ground.

' 2. In a vehicle wheel, the combination of ground penetrating membersadapted tobe brought successively in contact with. -the ground, manuallyoperated means-for moving said membersy into operative position, meansfor withdrawing said membersfrom their operative position, means forsuccessively locking said members in operative position by the rotativeforce of the wheel as said members are brought into contact with theground, and means for successively releasing said looking means as theindividual ground penetrating members are withdrawn from the ground.

3. In a vehicle Wheel, the combination with the tread member, of aplurality of ground penetrating members adapted to be broughtsuccessively in contact with' the ground, said members being movableinto and out of operative position, manually controlled means for movingsaid members into their operative position Iand 'mea-ns for locking saidmembers to the tread member in their operative position by the rotativeforce of the wheel.

4. In a vehicle wheel, the combination of the rim, and groundpenetrating members adapted to be revolved about an axis coincident withthe axis of the wheel, whereby they are successively brought intocontact with the ground, said wheel yand rim being free to rotate to alimited extent independently of said members when the latter are broughtinto contact with the ground, each of said members having a recesstherein facing in a direction opposite to that in which the rim isrotated, said recesses being in alinement with the rim, whereby therotative force of the wheel will force the rim into said recesses as theground penetrating members are successively brought into contact withthe ground to lock said members in operativeV position.

y5. In a vehicle Wheel, the combination of- .Wit the ground, said wheeland rim being free .to rotate to a limited extent independ? ently ofsaid members when the latter are brought into contact with the ground,and a locki penetrating members in alinement with the rim, whereby therotativeforce of the wheel will advance the rim into engagement withsaid locking members as the penetrating members are successively broughtin contactv with the ground to lock the latter-members in operativeposition.

6. In a vehicleWheel, the combination vof the rim carried thereby,ground penetrating members normally posltioned i within the treadsurface of the rim and adapted to be revolved about an axis coincidentwith the memberI formed on each of said axis of the wheel, whereby theyare successively brought in contact with the ground, said wheel beingfree to rotate to a limited extent independently of said members whenthe latter are brought in contact with' the ground, each of said membershaving a recess therein facing in a direction opposite to that in whichthe rim and Wheel is rotated, and means for moving said vground,v

penetrating members to project them beyond the tread surface of the rimand the recesses in alinement with the rim, whereby the rotative forceof the Wheel and rim will advance said rim into the recesses in therotate to a limited extent independently of said members, a lockingmember formed on each of the ground penetrating members adapted to bemoved into alinement with the rim when the ground penetrating membersare projected into operative position, and means for yieldinglyretaining the locking members and rim out of engagement, said yieldingretaining means being adapted to be overcome by the rotative force ofthe wheel when the round penetrating members are in contact w1th theground` 8. In a vehicle' Wheel, the combination With the tread member,of movable ground penetrating members normally positioned Within thetread surface of the tread member, an expansible member cooperating Withthe ground penetrating members, and means for expandmg said expansiblemember to move the ground penetrating vmembers beyond the tread surfaceof the tread members.

9. In a vehicle Wheel, the combination with the rim, of radially movableground penetrating members normally ositioned within the tread surfaceof the rlm, an expansible member coperating with the ground penetratingmembers, means for expanding said expansible member to project theground penetrating members beyond the tread surface of the rim intooperative posij tion, said ground penetrating members being adapted tobe revolved about an axis coincident with the axis of the rim and Wheel,whereby they are brought successively into contact With the ground, andmeans for successively locking the ground penetrating members inoperative position by the rotative forceof the rim as said members comein contact with the ground.

10. In a vehicle Wheel, the combination with the rim, of radiallymovable ground penetrating members normally posltioned within the treadsurface of the rim means for yeldingly retaining said mem ers in theirnormal position, an expansible member coperating With theground-penetrating members, means for yieldingly holding the to berevolved about an axis coincident with' the axis of the rim and Wheel,whereby thev are brought successive] into Contact Wit the ground, andmeans or successively locking the ground penetrating members in oerative position by the rotative force of tllie rim, as said memberscome in contact With the ground.

l1. In a vehicle Wheel, the combination with the rim, of radiallymovable round penetrating members normally positioned Within the treadsurface of the rim, an expansible member cooperating' With the groundpenetrating members, meansv for yieldingly holding the expansible membercontracted, means for expanding said member to project the penetratingmembers into operative position beyond the tread surface of the rim, alocking member formed on. each of the ground penetrating members adaptedto be moved into alinement with the rim when the ground penetratingmembers are projected into operative position, and means for yieldinglyretaining the locking members and rim out of' engagement, said yieldingretaining means'being adapted to be overcome by the rotative'force ofthe Wheel when the ground penetrating members are in contact with theground.

ARTHUR-L L. FITZ GIBBON.

